Idaho doomsday author Chad Daybell has been given the death penalty for killing two of his second wife's children and his first wife.

The sentence was reached unanimously by an Idaho jury and handed down June 1, two days after the 55-year-old was found guilty of murder in the killings of his spouse Lori Vallow Daybell's daughter Tylee Ryan, 16, and son Joshua "JJ" Vallow, 7, and his first wife Tammy Douglas Daybell, 49. 

Chad declined to make a statement, NBC News reported, while the Tammy Douglas Daybell Foundation responded to the sentence on social media.

"We want to thank everyone who put in countless hours of work to get where we are today; law enforcement, the prosecution, the media, and all of you who watched and listened to the trial and prayed for us," the group said on Facebook, adding, "We can all start to heal from the terrible losses we have suffered. We will miss Tammy every single day of our lives but we have some comfort knowing we will see her again."

Chad, who had self-published several doomsday-themed novels, was found guilty at a May 30 hearing of a total of three counts of first-degree murder, two counts of conspiracy to commit first-degree murder and grand theft by deception, one count of conspiracy to commit first-degree murder and two counts of insurance fraud.

His verdict and death sentence comes almost a year after Lori was sentenced to three consecutive life terms in prison without parole for her role in the murders. Both had pleaded not guilty in their cases.

Chad's triple murder trial began in April, with prosecutors saying in opening statements that he is someone with a "desire for sex, money and power" and who labels people standing in the way of his dreams as "zombies" and "dark spirits," NBC News reported.

The author was arrested in June 2020 after police uncovered the remains of the kids on his property in Idaho. They were last spotted in September 2019.

Tammy died one month later in the Idaho home she shared with her husband and their children, Garth Daybell, 32, and Emma Murray, 30. Chad and Lori married the following November. Tammy's death was originally considered to be from natural causes, but after her remains were exhumed that December, an autopsy determined she was killed by asphyxiation in a homicide, NBC News reported.

Chad and Lori, 50 were both indicted for murder in the deaths of the children in 2021. Court documents obtained by NBC News said Joshua was buried in a pet cemetery and Tylee's remains were dismembered and burned in a fire pit. The grand jury also indicted Lori for grand theft related to Social Security survivor benefits in connection to her deceased children, and indicted Chad for insurance fraud related to a life insurance policy he received benefits from after Tammy's death.

The disappearance and deaths of Tylee and Joshua were the focus of the 2022 Netflix documentary Sins of Our Mother, which featured an interview with Lori's eldest son, Colby Ryan. The 28-year-old also testified against his mother and stepfather in their trials.

"I stand here today, motherless, fatherless, sisterless and brotherless," he said at Chad's sentencing. "The only course forward is to trust in Christ, knowing that he has them in his arms. And wait for the day that we all meet again."

(E! and NBC News are part of the NBCUniversal family.)

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